This article explains what Uplink Failure Detection (UFD) is and how to configure it on Dell Networking Force10 switches.
How Uplink Failure Detection Works
- How Uplink Failure Detection Works
- Important Points to Remember
- How to configure Uplink Failure Detection
- Verify Uplilnk State Group status
An interface in an uplink-state group can be a physical interface or a port-channel (LAG) aggregation of physical interfaces.
An enabled uplink-state group tracks the state of all assigned upstream interfaces. Failure on an upstream interface results in the automatic disabling of downstream interfaces in the uplink-state group. As a result, downstream devices can execute the protection or recovery procedures they have in place to establish alternate connectivity paths. As shown in the following illustration.
Important Points to Remember
How to configure Uplink Failure Detection
- You can configure up to 16 uplink-state groups. By default, no uplink-state groups are created.
- An uplink-state group is considered to be operationally up if it has at least one upstream interface in the Link-Up state.
- An uplink-state group is considered to be operationally down if it has no upstream interfaces in the Link-Up state. No uplink-state tracking is performed when a group is disabled or in an Operationally Down state.
- You can assign physical port or port-channel interfaces to an uplink-state group.
- You can assign an interface to only one uplink-state group. Configure each interface assigned to an uplink-state group as either an upstream or downstream interface, but not both.
- You can assign individual member ports of a port channel to the group. An uplink-state group can contain either the member ports of a port channel or the port channel itself, but not both.
- If you assign a port channel as an upstream interface, the port channel interface enters a Link-Down state when the number of port-channel member interfaces in a Link-Up state drops below the configured minimum number of members parameter.
- If one of the upstream interfaces in an uplink-state group goes down, either a user-configurable set of downstream ports or all the downstream ports in the group are put in an Operationally Down state with an UFD Disabled error. The order in which downstream ports are disabled is from the lowest numbered port to the highest.
- If one of the upstream interfaces in an uplink-state group that was down comes up, the set of UFD-disabled downstream ports (which were previously disabled due to this upstream port going down) is brought up and the UFD Disabled error is cleared.
- If you disable an uplink-state group, the downstream interfaces are not disabled regardless of the state of the upstream interfaces.
- If an uplink-state group has no upstream interfaces assigned, you cannot disable downstream interfaces when an upstream link goes down.
- To enable the debug messages for events related to a specified uplink-state group or all groups, use the debug uplink-state-group [group-id] command, where the group-id is from 1 to 16.
- To turn off debugging event messages, use the no debug uplink-state-group [group-id] command.
Verify Uplink State Group status
||Enter configuration mode.
|FTOS(conf)# uplink-state-group 1
||Create and enable a group for tracking of the links. Group-id values are from 1 to 16.
|FTOS(conf)# no uplink-state-group 1
||Removes/deletes the uplink state group.
|FTOS(conf-uplink-state-group-1)# upstream te 0/40
FTOS(conf-uplink-state-group-1)# downstream te 0/1
|Assign a port or port-channel to the uplink state group as an upstream or downstream port.
|FTOS(conf-uplink-state-group-1)# downstream disable links < number | all >
||Configure the number of downstream links in the group the will be disabled (OPER Down state) if one upstream link in the group goes down. Default is no downstream links are disabled.
NOTE: Downstream interfaces in an uplink state group are put into a Link-Down state with an UFD-Disabled error message only when all upstream interfaces in the group go down.
|FTOS(conf-uplink-state-group-1)# downstream auto-recover
||(Optional) Enable so that UFD-disabled downstream ports in the uplink state group come up when a disabled upstream port in the group comes back up.
|FTOS(conf-uplink-state-group-1)# description <text>
||(Optional) Labels the uplink state group with a specific description.
|FTOS(conf-uplink-state-group-1)# no enable
||Disables upstream-link tracking without deleting the uplink state group.
FTOS# show uplink-state-group
Uplink State Group: 1 Status: Enabled, Up
FTOS# sho uplink-state-group detail
(UP): Interface up (Dwn): Interface down (Dis): Interface disabled
Uplink State Group : 1 Status: Enabled, UP
Upstream Interfaces : Te 0/40 (Up)
Downstream Interfaces : Te 0/1 (UP)
Example of port that has been disable due to uplink state upstream failure.
FTOS# show interfaces tengigabit 0/1
TenGigabitEthernet 0/1 is up, line protocol is down (error-disabled[UFD])